7 2.OA.1 Standard Explanation and Example2.OA.1. Word problems that are connected to students’ lives can be used to develop fluency with addition and subtraction. Table 1 describes the four different addition and subtraction situations and their relationship to the position of the unknown.Examples:• Take-from example: David had 63 stickers. He gave 37 to Susan. How many stickers does David have now? 63 – 37 =• Add to example: David had $37. His grandpa gave him some money for his birthday. Now he has $63. How much money did David’s grandpa give him? $37 + = $63• Compare example: David has 63 stickers. Susan has 37 stickers. How many more stickers does David have than Susan? 63 – 37 = o Even though the modeling of the two problems above is different, the equation, = ?, can represent both situations (How many more do I need to make 63?)• Take-from (Start Unknown) David had some stickers. He gave 37 to Susan. Now he has 26 stickers. How many stickers did David have before? - 37 = 26It is important to attend to the difficulty level of the problem situations in relation to the position of the unknown.• Result Unknown problems are the least complex for students followed by Total Unknown and Difference Unknown.• The next level of difficulty includes Change Unknown, Addend Unknown, followed by Bigger Unknown.• The most difficult are Start Unknown, Both Addends Unknown, and Smaller Unknown.Second grade students should work on ALL problem types regardless of the level of difficulty. Students can use interactive whiteboard or document camera to demonstrate and justify their thinking.This standard focuses on developing an algebraic representation of a word problem through addition and subtraction --the intent is not to introduce traditional algorithms or rules.2.OA.1. Use addition and subtraction within 100 to solve one- and two-step word problems involving situations of adding to, taking from, putting together, taking apart, and comparing, with unknowns in all positions, e.g., by using drawings and equations with a symbol for the unknown number to represent the problem.What are we asking students to do?What is the conceptual understanding that is needed?What does mastery look like?

8 2.OA.2StandardExplanation and Example2.OA.2. This standard is strongly connected to all the standards in this domain. It focuses on students being able to fluently add and subtract numbers to 20. Adding and subtracting fluently refers to knowledge of procedures, knowledge of when and how to use them appropriately, and skill in performing them flexibly, accurately, and efficiently.Mental strategies help students make sense of number relationships as they are adding and subtracting within 20. The ability to calculate mentally with efficiency is very important for all students. Mental strategies may include the following:• Counting on• Making tens (9 + 7 = )• Decomposing a number leading to a ten ( 14 – 6 = 14 – 4 – 2 = 10 – 2 = 8)• Fact families (8 + 5 = 13 is the same as = 5)• Doubles• Doubles plus one (7 + 8 = )However, the use of objects, diagrams, or interactive whiteboards, and various strategies will help students develop fluency.2.OA.2. Fluently add and subtract within 20 using mental strategies. By end of Grade 2, know from memory all sums of two one-digit numbers.What are we asking students to do?What is the conceptual understanding that is needed?What does mastery look like?

9 2.NBT.9StandardExplanation and Example2.NBT.9. Explain why addition and subtraction strategies work, using place value and the properties of operations.2.NBT.9. Students need multiple opportunities explaining their addition and subtraction thinking. Operations embedded within a meaningful context promote development of reasoning and justification.Example: Mason read 473 pages in June. He read 227 pages in July. How many pages did Mason read altogether?• Karla’s explanation: = _____. I added the ones together (3 + 7) and got 10. Then I added the tens together ( ) and got 90. I knew that was 600. So I added for 100 and added and found out that Mason had read 700 pages altogether.• Debbie’s explanation: = ______. I started by adding 200 to 473 and got 673. Then I added 20 to 673 and I got 693 and finally I added 7 to 693 and I knew that Mason had read 700 pages altogether. • Becky’s explanation: I used base ten blocks on a base ten mat to help me solve this problem. I added 3 ones (units) plus 7 ones and got 10 ones which made one ten. I moved the 1 ten to the tens place. I then added 7 tens rods plus 2 tens rods plus 1 tens rod and got 10 tens or 100. I moved the 1 hundred to the hundreds place. Then I added 4 hundreds plus 2 hundreds plus 1 hundred and got 7 hundreds or 700. So Mason read 700 books.Students should be able to connect different representations and explain the connections. Representations can include numbers, words (including mathematical language), pictures, number lines, and/or physical objects. Students should be able to use any/all of these representations as needed.An interactive whiteboard or document camera can be used to help students develop and explain their thinking.What are we asking students to do?What is the conceptual understanding that is needed?What does mastery look like?

10 Unit 1 Work Groups EDM/Math Trailblazers alignmentUsing the correlation documents and your experience, identify which lessons/activities align to this unitAdditional resources alignmentUsing the additional resources, identify which lessons/activities align to this unitInternet resourcesUsing the suggested resources and others you identify, find lessons/activities that align to this unitLessonsUsing the lesson template, record any lessons you have used or would like to use that align to this unitInterdisciplinary activities/lessonsSpecialists – how can you address the standards in this unit in the work that you do?

11 Review of Resources/Materials to PurchaseReview instructional materialsThoughtsAdditionsTake the Classroom Resources survey on P21Make sure to choose Grade Two!Look at the Stage 3 Resources. Have teachers look at the suggested materials and resources for quality.Brainstorm additional – keep a list of their ideas with as much detail as possible.